Supercritical Helium Cooling of Hollow Superconductors

Abstract

A research program is currently in progress to examine the physical characteristics of hollow composite superconductors cooled by an internal flow of supercritical helium. This type of superconducting device has been proposed for producing the high magnetic field intensity in a large cryogenic bubble chamber [1]. The principal thermal problem associated with the design of a hollow-conductor superconducting magnet is to provide total refrigeration sufficient to maintain an equilibrium temperature below the critical throughout the coil. This refrigerant capacity must also have sufficient built-in margin to combat thermal instabilities caused by flux jumping [2].